Automatic bag feeding machine



J. D. HELM ETAL AUTOMATIC BAG FEEDING MACHINE Aug. 28, 1962 3,050,918

Filed April 16, 1959 14 Sheets-Sheet 1 I I I I I I I I BJCK INVENTORS Jim- D. HELM FRANK 4. #OPK/IVS Arrazwzr:

Aug. 28, 1962 J. D. HELM ETAL 3,050,918

AUTOMATIC BAG FEEDING MACHINE Filed April 16, 1959 14 Sheets-Sheet 2 FIG. 5'

Jrfaa wars A 28, 1952 J. D. HELM ETAL 3,050,918

AUTOMATIC BAG FEEDING MACHINE Filed April 16, 1959 14 Sheets-Sheet 3 INVENTORS J'Ack -D. flaur FRANK A. fiOPklfl/S g- 28, 1962 J. D. HELM ETAL 3,050,918

AUTOMATIC BAG FEEDING MACHINE Filed April 16, 1959 14 Sheets-Sheet 5 is E m INVENTORS .74 an: D. l/azn Flea/we A. l/onmvs B YMY'yM 1962 J. D. HELM ET AL 3,050,918

AUTOMATIC BAG FEEDING MACHINE Filed April 16, 1959 14 Sheets-Sheet 6 FIG: '7

INVENTORS Tack D. A e-2M FEAA/K 4. f/ xms' BV Wh/YW Jrramvar;

Aug. 1962 J. D. HELM EIAL 3,050,918

AUTOMATIC BAG FEEDING MACHINE Filed April 16, 1959 F25: a I T- 14 Sheets-Sheet '7 lrrokmers Aug. 28, 1962 J. D. HELM ErAL 3,050,918

AUTOMATIC BAG FEEDING MACHINE Filed April 16, 1959 14 Sheets-Sheet 8 FIG 5 INVENTORS JACK D- 6454M FRANK A. l/aPk/MS Jrrmwsn 1962 J. D HELM EIAL 3,050,918

AUTOMATIC BAG FEEDING MACHINE Filed April l6, 1959 14 Sheets-Sheet 9 FIE1U 20 2o 74 3 INVENTORS JZCK D. f/EZM PRmvK 4. HOPKINS BYQWW Arrogqen;

Aug. 28, 1962 Filed April 16, 1959 J. D. HELM EI'AL AUTOMATIC BAG FEEDING MACHINE 14 Sheets-Sheet 1O IHI' ll lll ENTORS J79 6K .0. 1/54 FRANK A. l/OPAIMS Arronvzrs g- 28, 1962 J. D. HELM ETAL 3,050,918

AUTOMATIC BAG FEEDING MACHINE Filed April 16, 1959 14 Sheets-Sheet 11 Pas/rm FORMIRD INVENTORS J'A me D. HELM f'xmvx 4. l/orxnvs 477'oawers Aug. 28, 1962 J. D HELM ETAL 3,050,913

AUTOMATIC BAG FEEDING MACHINE Filed April 16, 1959 14 Sheets-Sheet 12 E mHmHh INVENTORS Jiwc D. HEAM Pam/x4. l/a xwvs Aug. 28, 1962 J. D. HELM ETAL AUTOMATIC BAG FEEDING MACHINE Filed April 16, 1959 14 Sheets-Sheet 14 SEQUENCE 78:44?

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70 SCALE INVENTORS PQNER Jhc D. Ila-4M PRJA/K L. flan ms drrazzmsxs United States Patent 3,050,918 AUTOMATIC BAG FEEDING MACHINE Jack D. Helm and Frank L. Hopkins, Minneapolis, M1n1 1., assignors to Bemis Bro. Bag Company, Minneapolis, Minn., a corporation of Missouri Filed Apr. 16, 1959, Ser. No. 806,955 48 Claims. (Cl. 533$6} This invention relates to machines for handling the feeding and filling of large sizes of multiwall bags at high speeds. Heretofore there have not been available reliable machines for feeding multiwall bags at high speed and for filling them with free flowing products such as sugar, salt, fertilizers, chemicals, feeds, and the like.

In the handling of multiwall bags of large sizes such as 25 pounds, 50 pounds, 100' pounds, and the like, the dimensional sizes of the bags are quite large. Manipulating such bags, and insuring their adequate opening during the filling operation has been heretofore accomplished by hand except in certain large and cumbersome machines which operate at very slow speeds.

It is an object of this invention to provide a machine capable of handling large size multiwall bags and for filling them with free flowing material at a high rate of speed, as for example, fifteen per minute or greater speeds. It is anotherobject of this invention to provide a bag feeding and filling machine which is capable of automatic operation with only occasional attention of plant personnel.

It is still another object of this invention to provide a bag feeding and filling machine wherein the manipulation of the bag is coordinated with the filling of the bag and in sequence so that as one bag is filled another will be brought at least partially into position for manipulation into the filling relationship with the filling spout of the machine of this invention. It is a further object of this invention to provide an improved bag feeding and filling machine wherein the bag is fully opened so as to provide an unrestricted space into which the filling spout may be entered by coordinate movement, so as to provide for very rapid flow of the product therethrough during the filling operation. It is a still further object of the invention to provide an improved bag filling machine for handling large sizes of multiwall bags and for filling them without the need for providing shaking mecha nisms or the like to compact the product in the bag. It is another object of the invention to provide a large fastoperating bag feeding and filling machine which is compact and which can be built and operated at lower cost than mechanisms previously available.

Other and further objects are those inherent in the invention herein illustrated, described, and claimed and will be apparent as the description proceeds.

To the accomplishment of the foregoing and related ends this invention then comprises the features hereinafter fully described and particularly pointed out in the claims, the following description setting forth in detail certain illustrative embodiments of the invention, these being indicative however of but a few of the various ways in which the principles of the invention may be employed.

The invention is illustrated with reference to the drawings wherein:

FIGURE 1 is a plan View of the machine. For purpose of nomenclature the front of the machine is that side which is viewed in the direction of arrows 22 of FIG- URE 1 and the left side of the machine is as viewed in the direction of arrows 33. The front and left end of the machine are designated in FIGURE 1 and are also shown in the drawings. The right end and rear views of the machine are not illustrated;

FIGURE 2 is the front elevational view of the machine with the machine housing broken away and only a fragmentary portion of the magazine structure shown so as to illustrate some of the working parts of the machine, said View being taken along the line and looking in the direction of arrows 22 of FIGURE 1;

FIGURE 3 is a left end elevation of the machine as viewed along the line and looking in the direction of arrows 33 of FIGURE 1. In this view the bag magazine on which the bags are stacked preparatory to feeding and filling is not shown;

FIGURE 4 is a fragmentary enlarged vertical sectional view of the bottom portion of the filling hopper and spout, said view being taken along the line and in the direction of arrows 4-4 of FIGURE 3;

FIGURE 5 is an enlarged fragmentary horizontal sectional view of the filling spout and a plan view of the carriage on which the hopper-spout assembly is mounted, said view being taken along the line and in the direction of arrows 5-5 of FIGURE 4;

FIGURE 6 is an enlarged fragmentary left end elevational view of the filler hopper and spout and the bag clamp mechanism, said View being taken along the line and in the direction of arrows 66 of FIGURE 2;

FIGURE 6A is a fragmentary horizontal sectional view of the no bag-no product switch mechanism, said view looking in an upward direction and being taken along the line and in the direction of arrows 6A6A of FIGURE 6;

FIGURE 7 is a fragmentary enlarged vertical sectional view of a portion of FIGURE 1 showing certain of the working parts of the machine in greater detail, said view taken along the line and in the direction of arrows 77 of FIGURE 1;

FIGURE 8 is a small plan view corresponding to FIGURE 1, part of the cabinet being broken away to better illustrate certain working portions of the machine. Many parts are left out of this view for purposes of simplification, said view being included primarily to illustrate the location of the machine at which various sectional lines for the ensuing sectional view, FIGURES 9-14, were taken;

FIGURE 9 is a vertical sectional view taken along the line and in the direction of arrows 9-9 of FIGURE 8 to illustrate the bag lift mechanisms and portions of the cam drive;

FIGURE 10 is a fragmentary vertical sectional View corresponding to FIGURE 9 of the bag top clamp mechanism and a cam and lover drive for said mechanism as well as certain other parts of the machine of FIGURE 8, said view being taken along the line and in the direction of the arrows 1010 of FIGURE 8;

FIGURE 11 is a fragmentary vertical sectional View taken along the line and in the direction of arrows 11,-11 of FIGURE 8 to show the bag pick-up mechanism, its drive cam, and related mechanism;

FIGURES 12 and 13 are related views showing the bag opening mechanism and associated mechanism. FIG- URE 12 is a fragmentary vertical sectional View taken along the line and in the direction of arrows 12-12 of FIGURE 8, and FIGURE 13 is a fragmentary vertical sectional view taken along the line and in the direction of arrows 13-43 of FIGURE 8. In this connection it should be recalled that the sectional View in FIGURE 12. is in a fore and aft direction corresponding to FIGURES 9, 10, and 11, whereas FIGURE 13 is in a transverse direction;

FIGURE 14 is a vertical transverse sectional view taken along the line and in the direction of arrows 14-14 of FIGURE 8 to show the hopper transfer drive mechanism and interlinking parts, and also to show the bag pick-up mechanism in elevation. The hopper and spout are shown at the dumping station in solid lines and at the loading station in dotted lines;

FIGURE 15 is a very much simplified plan view illusof operation of the various elements of the machine.

Referring to the drawings, the bag feeding, opening, and filling machine has a rectangular frame housing 28 in which the drive mechanisms of the machine are contained. The housing is in part made up of a plurality of panels 23 mounted on appropriate structural frame members, said frame members including a base 21, vertical "members 19, 22, 24, 25, 26, and 27, and a top frame 28. The four corner frame members 22, 25, 26, and 27, together with the base 21 and the top 28 form a rectangular housing containing the drive motors, gear boxes, cams and other drive machinery.

For approximately one-half of the distance from the back toward the front, and extending from the left side of the rectangular housing 28, there is an overhanging frame member which is the portion shown under the bracket 29 in FIGURES l, 2, 3, and 14. This overhanging frame covers the space into which the unopened bags are moved from the bag magazine shown generally opposite the bracket 30 in FIGURE 1, and in which the bags are opened, lifted on the spout, clamped to the spout, and then transported with the spout to a delivery position, and simultaneously filled, preparatory to being dropped onto the receiving end of the conveyor, generally designated 31.

The bag magazine 30 forms a bag rack and conveyor that provides for holding vertically stacked unopened bags in a flat condition with the open ends of the bags up, and for moving the stacked bags 39 in the direction of arrow 3 11 with gentle pressure on the stacks to a certain position which is the feed line, FL as shown in FIGURE 3. At the feed line, the end bag in the stack is lightly held along the vertical side edges of the bag by retaining means which forms part of the bag magazine, and if needed, at the top edge of the bag, by additional retaining means, said retaining means not being illustrated in the drawings. The bags are held only enough so as to retain the bags in a stacked condition and still permit the endmost bag in the stack to be removed by a pull on its left surface in its central area, the pull being imposed by vacuum devices which will be described hereinafter. It is sufiicient for the purposes of this disclosure to say that the stack of bags presents the end bag in a vertical plane and that it can be removed from the stack by vacuum applied to the face of the bag, the motion of removal being in the direction of arrow 311 of FIGURE 1.

In FIGURE 1 the bag feed and opening station, and the place where the bag is lifted upward and clamped onto the spout 45 is generally denoted the loading station LS. At this station a bag 40 is attached to the lower end of a spout and filling is begun as the spout is transported to the dumping or delivery station which for purposes of reference is denoted DS. The delivery station is directly over the receiving end of the conveyor 31 which is positioned so that it is slightly below the bottom of the bag after the bag is filled. At the delivery station DS, the filled bag is released from the spout, drops a short distance to the conveyor, and is then moved away from the machine by the conveyor in the direction of arrow 32. It may be noted parenthetically that the filling of the bag is accomplished during the movement of the spout-hopper mechanism 38, from the loading station LS to the delivery station DS, and that meanwhile the bag feeding and opening mechanisms are picking up another bag, opening the top of the bag, and beginning to lift it preparatory to affixing the bag to the lower end of the spout as the spout is returned to the loading station.

This functional plan of the machine, thus generally described is accomplished by means of a plurality of interrelated mechanisms, some of which are directly driven by cams and leverages, and others driven pneumatically, all in properly timed sequence. The weighing of the charge which is filled into the bag is accomplished by a separate machine (not shown). The weighed charge is dumped into the hopper 38 of the bag opener and filler machine covered by this invention in properly timed sequence as will become apparent hereinafter. Stated otherwise, the hopper spout mechanism of the present invention does not, and is not intended to, weigh and value the delivery of the charge being filled. These functions are accomplished by separate machines forming no part of the present invention.

Motor Drive and Cam System Referring to FIGURES 2, 3, 7, 8, l1, and 15, within the main frame there is provided a motor The motor 68 has an output sprocket 63 that is connected through the chain 64 which goes around the idler 67 to the driven sprocket on the input shaft of the gear box 71 (see FIGURE 8).

The shaft 78 is extended at 68, outside the machine and is provided with a smooth-rimmed handwheel 69, said extension being connected through mechanism (not shown) that is alternately engaged and disengaged with the shaft to drivingly disconnect and connect said handwheel to the shaft. When desired, the handwheel 69 and its shaft 68 can be engaged by mechanism (not shown) so as to turn the sprocket 65 and the shaft 70 for moving the machine mechanism a short distance by hand. Also in the machine, there is provided a vacuum pump 66 which is driven by a separate motor. The gear boX 71 is provided with angle gears 72, 74 which drive the angularly positioned shaft 75. Secured on the shaft 75 are the sprocket 76 and the coupling 77. Secured to the opposite end of the coupling is the shaft 7 5A which serves to mount and rotate the cams C5 and C6, the outer end of the shaft 75 being supported in a suitable bearing 78 which is mounted on the frame.

The sprocket 76 is connected by means of the chain 81 (see FIGURE 15) to a driven sprocket 82 on the shaft 84. Upon shaft 84 there are mounted cams C7 through C12, which are shown in FIGURE 17. These cams, Which are relatively much smaller than the cams C1 through C6, serve to control the operation of the electrical-pneumatic portions of the machine.

The shaft 70 extends through the gear box housing 71 and is connected through the coupling '86 to the shaft 87 which has its outer end supported in bearing 88. The

shaft 87 serves as a mounting for the spaced cams C1 through 04. All of the cams C1 through C6 serve to directly operate mechanical portions of the machine, and since the shafts 75A and 87 are geared together, the mechanisms operated by the cams C1 through C6 are moved in timed sequence according to the shape of the cams. By the same token, the drive consisting of the sprockets '76 and 82 and the chain 81 for driving the shaft 84, operates the cams C7 through C12 in timed sequence. The sequence of operation of cams C7 through C12 is timedrelated to the operation of the cams C1-C6 and thus all of the mechanisms operated by cams C7 through C12 are accordingly moved in precise timed-relation with the mechanisms operated by the cams C1 through C6.

H upper-Spout Mechanism The top of the machine which consists of the frame 28 is extended, as previously mentioned, so as to provide the overhanging portion shown under the bracket 29 (see FIGURES l, 2, 6, 10). This overhanging portion is composed of a strong rectangular frame having at its back side a channel member 33, and at the front side a strong channel member 34. These are tied together at t e end by the channel section 35. Over the top of the frame 33, 34, and 35 there is provided a housing 36 which is neatly curved so as to cover the mechanisms underneath. A slot 37 (as shown in FIGURE 1) having a width W and a length LL is formed in the housing 36 to provide suitable clearance to have the lower portion of the hopper 38 extended therethrough. Within the confines of the frame 33-34-35, there are mounted two parallel rods 42 and 43 which extend transversely of the machine (that is to say in the direction of dimension line LL of FIG- URE 1). These rods form slideways on which a carriage frame, generally designated 44, is adapted to move back and forth (see FIGURES 4, 5, and 6). This carriage frame serves to mount the hopper 38, the lower end of which is provided with a spout 45 having a cross sectional shape as shown in FIGURE 1. This spout is flattened at the ends but has a generally outwardly convex curved front and back and is shaped to more or less fit the shape of the top of a multiwall paper bag when the top portion of the bag is opened, said bag having gussets 40a, infold line 40b, and fold lines 400. That is, the spout has an inwardly V-notch portion 45d on either side shaped so that the gussets 40a will readily fit thereover (see FIG- URE 6).

The movement of the carriage 44 back and forth from and to the loading station and delivery station is accomplished by a drag link 46 (see FIGURE 14) which is pivotally connected at 47 to the carriage 44. The opposite end of the drag link is pivotally connected at 48 to the upper end of a lever arm 49 which in turn is pivoted at 50 to the cross-frame member 51, the cross frame member forming a part of the main frame. On the lever arm 49 there is mounted a cam follower 52 which works in the cam track 54 of the cam C5. The team C5 is mounted on the main shaft 87 and is rotated as previously described. Accordingly, as the shaft 87 turns, the arm 49 is swung back and forth in the direction of the double arrow 57 from the return position shown in dotted lines in FIG- URE 14 to the forward position shown in full lines in the same figure. Accordingly, the carriage 44 and the hopper-spout, and all mechanisms attached to that carriage are moved backward and forward as previously described.

Bag Pick-Up Arm Assembly (Cams C4 and C9) Referring to FIGURES 1, 2, 3, 11, and 14, the bag pick-up mechanism 90 comprises a stiff subsidiary frame 92 which projects to the left (as shown in FIGURES 1, 2, and 14) from the main frame housing 20 at a level somewhat elevated above floor level, This frame is provided with bearings 94 and 95 which serve to mount the shaft 96 for a slight angular rotation. There is keyed on the right end of the shaft 96 (as shown in FIGURE 14) an operating arm 98, the upper end of this arm being pivotally connected at 99 to the drag link 100. The opposite end of the drag link 100 (see FIGURE 11) is pivotally connected at 101 to the lower end of a lever 102, the upper end of this lever being rotatably mounted on the shaft 104 which is stationarily mounted in bearings 105. The bearings 105 are mounted on a frame member 106 within the machine frame 20.

The lever 102 has a cam follower 108 that works in the cam slot 109 in the cam C4. The cam C4, it will be remembered, is mounted on the shaft 87 and accordingly therefore as the cam C4 is rotated the lever 102 moves from the In position in which the bag is engaged and picked up, to the Return position where the bag is held, preparatory to being opened, and subsequently lifted directly upwardly onto the spout 45.

Referring to FIGURES 3 and 14 in particular, the outer end of the shaft 96 is provided with a main bag pick-up arm 110, which is keyed to the shaft. This arm, at its upper end, is provided with a pivot 111, as shown in FIGURES 3 and 11, and upon this pivot there is mounted a bracket arm 112. The arm 112 extends to 6 the rear of the machine as shown in FIGURES 3 and 11 and at its rear end is provided with a pivot 114 to which the upper eye end of the tie rod 115 is attached, the lower end of the tie rod 115 being provided with a clevis 116 which is connected to the subsidiary frame 92 by pivot 117.

The lower eye 116 is made so that it can be threaded onto the rod 115 and when adjusted, held in place by a suitable locking nut, so as to allow careful adjustment of the arm 112. The distance between the center lines of the shaft 96 and pivot 117 is the same as the distance between :the center line of the pivots 111 and 114; and accordingly the arm and the tie rod are of a length to act as a parallelogram of motion whereby the bracket arm 112 is therefore always kept at a given angle with reference to base, as it is swung around an arc as defined by the arm 110.

The front end of the bracket arm 112 has a downwardly extending integral portion 119 and at the lower end of this portion there is mounted -a suction device 120 in the form of a vacuum cup having a central area through which the suction is applied. At the upper portion of the bracket composed of members 112 and 119 there is mounted a cross piece 121 which serves to support two spaced suction devices 112A and 122B (see FIGURE 14). These suction devices may also provide for application of suction throughout a prescribed area. The three suction devices 122A, 122B, and 120 are thus carried by the frame 112-119 and when the shaft 96 is rotated clockwise as shown in FIGURES 3 and 11, the suction devices are moved to an In position so that the front or effective surface of the suction devices are pressed against the end bag in the stack of bags, said end bag being located at the feed line (see FIGURE 11). The end bag thus engaged by the suction devices will be pulled away from the remaining :bags in the stack and moved back to Intermediate Position IP as defined by the movement of suction devices, shown in dotted lines in FIGURE 12. In this position, the bag is in a vertical plane but as yet the top of the bag is not spread apart for feeding it on to the spout 45. The timing of the application of suction to the suction devices is accomplished by means of c am C9, as will be described.

Bag Opening Assembly (Cams C3 and C11) To accomplish the opening of the top of the bag preparatory to lifting it onto the spout 45, there is provided another vacuum device, and related mechanism generally designated 124, as shown in FIGURES 2, 3, 12, and 13. Upon the lower frame 21 there is provided an outwardly extending angular perch 21A which therefore becomes a part of the bottom frame. Upon the frame 2121a there are mounted two bearings 125 and 126 in which a shaft 128 is mounted for limited rotation. Within the frame portion 21, and on the shaft 128 there is mounted an operating arm 129, which, at its upper end, is provided with a pivot 130 that is connected to a drag link 131. The drag link is provided with a screw adjustment 132 by means of which the effective length thereof may be changed. This drag link is of circular cross section outside the area of the cam C3, see FIGURE 12, but within the general area of the cam C3 the link is provided with a rectangular cross section 131a which has an elongated slot. 134 positioned so that the shaft 87 passes through said slot. The link 131 then continues to the right as shown in FIGURE 12 and at its right end is provided with a cam follower 135 which works in the cam slot 136 in the cam C3. Accordingly, as the cam C3 is rotated by the shaft 87, the arm 129 is moved in and out from and to the dotted and full line positions as shown in FIGURE 12.

At the left end of shaft 128 as shown in FIGURES 7 and 13 there is keyed-on a fitting 138 which is shaped so as to provide spaced mountings 138A and 13813 for receiving a fixed pivot shaft 139 therein. On this pivot shaft there is in turn mounted the lower widened end of bag opening arm 140. Accordingly, the bag opening arm can swing on the pivot shaft 139 to and from the forward and return positions as shown in dotted lines and full lines respectively in FIGURE 13. At the same time any rotation of shaft 128 imposes on the arm 140 a movement from and to the dotted and full line positions of 140, as shown in FIGURE 12.

The movement illustrated in FIGURE 12 is, as previously described, accomplished by rotation of the cam C3. The movement shown in FIGURE 13 is accomplished by cam C6, and its associated mechanism which will now be described. Upon the arm 140 at a position a little less than halfway upward along the arm from its bottom pivot 139 there is provided a secondary pivot 142 which is connected to the drag link M3. The right end of drag link 143, as shown in FIGURE 13, is connected through an eye 144- to the pivot 145 on a lever 146. The lever 146 is pivotally connected at 147 to the bracket 148 which in turn is mounted on the frame memher 149 of the main frame. The lever 146 has an upwardly extending end 146A that is biased in a clockwise direction by means of the spring 151 which is attached to the frame. On the lever 146 there is a cam follower 151 which rides on the exterior surface of the cam C6. Accordingly, as the cam C6 is rotated (due to the retation of shaft 75A) the cam follower 151 and arm 146 are caused to move. The movement of arm 146 is transmitted through the drag link 143 to impose a swinging movement upon the arm 140 to move said arm from and to the forward and return positions as shown in FIG- URE 13, spring acting to hold the cam follower 150 in contact with the cam C6.

At the upper end of the arm 140 there is a suction device 154, the timing of the application of suction through this device being accomplished by cam C11 as will be more fully described. Hence, after the bag has been picked up and moved by the suction devices 120 122A122B to the position of line IP in FIGURE 3, with the bag as yet unopened, the arm 140 with the suction device 154 on it, is swung from the return position to the forward position as shown in FIGURE 13, and the arm 140 is then moved from the Out position shown in FIGURE 12 in which it is clear of the bag, to the In position in which it engages the free face of the bag, as it is held in the unopened position at line 11 shown in FIGURES 3 and 12. At position IF the suction device 154 engages the still unopened bag. When the arm 140 and suction device 154 are then moved to the Out positions as shown in FIGURE 13, and the bag pick-up assembly 96 is moved to the return position (FIGURE 11), the top of the bag will be spread apart, this being preparatory to engagement of the top edges of the bag by spaced pairs of bag top clamps 193, preparatory to elevating the bag into position on the spout.

Bag Top Clamp and Bag Lift Arrangement Referring to FIGURES 3, 7, 9, and 10, the mechanism, generally designated 159, for engaging the partially spread-apart top walls of the bag and for then further spreading the said top walls and lifting the bag into registry with the bottom end of the spout 45 consists of a cross-shaped frame having a lower pivot 161 and an upper pivot 162a. The lower pivot is connected to the left end of a main lift arm 162. The right end of that arm is pivoted on the rock shaft 164 that is held in the bearings 165a, 1651) on the frame members 166a, 1661:. The arm 162 is in the form of a bell crank having a lower depending end 167 fitted with a cam follower 168 which rides in the cam groove 169 of the cam C1. Accordingly, as the cam C1 rotates the arm 162 is oscillated upwardly and downwardly in a direction of the double arrow 170 thereby moving the cross-shaped frame 160 correspondingly.

Upon the frame 166a there is a bracket 171 mounting a pivot 172 in vertical alignment with the center line of shaft 164 as viewed in FIGURES 3 and 9. It will be noted by reference to FIGURE 7 that this bracket 171 slants inwardly so that the pivot 172, and the link 1174- having its right end attached to it, are in vertical alignment above the bell-crank 162167. The left end of link 174 is connected to the pivot 162 of the crossshaped frame 160. The length of the link 174 is made adjustable and it is adjusted so that the dimension between the center lines of pivots 161 and 164 is the same as the dimension between the center lines of the pivots 162a and 172.. Accordingly, the cross-shaped frame is translated up and down along an arcuate path but its position always remains vertical as viewed in FIGURE 3. The upper position of the cross-shaped frame 161 is shown in FIGURES 3, 9, and 10, in full lines and in FIGURES 9 and 10 the lower position of the same frame is shown in dotted lines.

The cross-shaped frame has two pivots 176R and 176L mounted thereon which serve to pivotally support the generally upright bag clamp arms 177R and 177L. The arm 177R is provided at a point intermediate its ends with a pivot 1'78 to which a rod end bearing 179 is attached, the rod end bearing being on the tilt controller link 1811. The opposite end of the link 180 is pivotally attached at 181 to the upper end of a lever 182. which likewise is pivotally supported on the shaft 164. The lever 182 has a lower end 184 that is provided with a cam follower 185 which is adapted to ride in the cam groove 186 in cam CZ. Accordingly, the lever 182 is oscillated back and forth between the position shown in full lines and dotted lines in FIGURE 10. This movement is communicated to the bag clamp arm 177R. This arm has at its lower end a downwardly and inwardly extending portion 177]) which provides a pivot 188 to which an interconnecting link 189 is attached. This interconnecting link extends upwardly to a pivot 190 in the offset 191 on the arm 17'7L. Accordingly, any motions of the arm 177R with reference to the cross-shaped frame 166 are duplicated in an opposite sense by the motion of the arm 177L. The reason for this being that when the cross-shaped frame 166' is moved to its lowermost position as shown in dotted lines in FIGURES 9 and 10, the arms 177R and 177L are moved toward each other to a position appropriate for the bag clamps (which will be described) to grip the top of the spread apart bag, which at that time is still held by the suction devices 12ti122A-122B of the bag pick-up assembly and by the suction device 154 of the bag opening assembly. Then, after the clamps 193R, 193L on arms 177R and 177L have taken hold of the spread apart upper portions of the bag, the suction devices are deprived of their vacuum supply and are released from the bag, said bag then being held in a partially opened condition by the bag clamps. Then as the cross-shaped frame 160 is elevated, the arms 177R and 177L are moved slightly apart from each other by virtue of the combined motions of the parallelogram arms 162, 174 and the motion of the control arm 180. This further spreads apart the upper portion of the mouth of the bag so that it may easily slip over the spout 45.

The entire mechanism of arms 162 and links 174 and 180 as well as the cross-shaped frame 160 is within the dimensional confines of the frame 20, and the arms 177R and 177L likewise are within the confines of the frame 24 From the upper ends of each of the arms 177R and 17'7L, and fixedly attached thereto, is a pair of outwardly extending hollow tubes 199 which extend to the loading station LS (see FIGURE 7). Mounted for limited rotational movement in the respective hollow tubes are rods 192L, 192R. Each of the rods extends outwardly beyond its respective tube to mount a frame member 194, the rods being rotatably mounted in the frame members. Each frame member is prevented from rotating relative to its tube by being adjustably attached at 291 to the end of the adjacent hollow tube.

Each of the frame members have downwardly extending ears 195-195 on the inner surfaces of which (i.e. the surface which faces the spout 25) there is an area of rubber as shown in FIGURES 3, 9, and 10. The area of rubber is denoted 195R for the rods BZR, and l96L for the rod 1921.. The spaced ears l95-l95 each faced with rubber on the inside surface serve to engage the outer surface of each of the opposed bag walls.

"Opposite each of the ears 195-195 of each of the frames 194 there is provided a pair of clamp jaws 197 denoted 197R for the rod 122R and 2971 for the rod 192E These clamp jaws are spaced apart along the rod and are connected together so that they pivot as a unit to close against the opposing rubber faced areas 126lol96L. The frame members 1%, the clamp jaws l97R-l97L and their associated elements are considered the bag top clamps 1193.

The operation of the clamp jaws is accomplished by small air cylinders 128R, l98L. The air cylinder 19311 is pivotally connected at 1255?; to the offset 191 on the lower end of the arm 177%., and the piston in this cylinder is pivotally connected at Zililf. to the outer end of the radial arm 262, the inner end of said arm being keyed to rod 192R. The air cylinder 19% .c thus operates the pair of clamp jaws opposite the fixed ears 15 5 on the right side of the machine (i.e. toward the front). A11 exactly similar arrangement is provided for operating the clamp jaws 197L toward the back frame member. The clamp jaws 1971. are operated by the air cylinder 2.981, which is connected at its lower end to the same pivot 19%} to which the link 13? is connected and the piston rod in the cylinder 1981s is connected to the pivot ZililL. The pivot 20llL is mounted in the outer end of radial arm 232, the inner end of the arm being keyed to the rod 1921.. When the cylinders i 8R and have air injected into them, they move the clamping jaws 197R and l97L in a direction toward the ears 195R and ESL to bear against the rubber coated areas 196K and 196L thereby holding the upper edges of the bag mouth securely between said ears and said rubber coated areas.

The gripping action of the bag clamps upon the bag, as just described, takes place when the entire cross-frame 160 is in its lower, dotted line position as shown in FIG- URES 9 and 10, and the bag is thus gripped while still being held by the suction devices, as previously related. The suction devices are thereupon tie-energized and the bag is held mechanically by the bag clamp on the lift mechanism. The cross-frame 16% then is raised and simultaneously the arms 177R and 1771. are moved slightly apart thereby opening the bag mouth to a wider dimension so that it will easily slip onto the spout 45, which has meanwhile moved to the loading station LS. The bag mouth is thus slipped onto the spout 45. It will subsequently be held on the spout by other means, denoted bag holder jaws, and then the bag clamps will be released.

Bag Holder Jaws on Hopper-wont Arrangement The bag holder mechanism generally designated 205 for tightly holding the bag on the spout 455 is best shown in FIGURES 3, 4, 5, 6, and 6A. This mechanism is carried entirely by the carriage 44 which, as previously described, slides back and forth on the parallel rods 42 and 43. It is noted parenthetically that the shape of the spout 45, while being fairly flat at the right and left ends, as shown in section in FIGURE 5, yet contains an inward V-notch 45d of increasing de th as viewed in FIGURES 3 and 6. The reason for this being that bags for which this particular spout is shaped are known as in-fold bags, and the notch provides a clearance space at the lower end of the spout. Normally however, the opened bags, even though the in-fold is still not completely withdrawn, will have sufficient space so as to ll) easily slip onto the spout. After the bag has been brought to the level shown in FIGURE 6 by means of the bag clamps and lift mechanism on the cross-shaped frame lot}, as previously described, the bag is then clamped tightly to the spout by the mechanism which will now be described.

On the carriage frame 44, at either side are mounted spaced pivot rods ZiltiL and 2tl6R. At the left end of these rods, when the machine is viewed, and as shown in FIGURES 4 and 5, there are provided bag holder jaws 226, 227 which include lever 208 (for rod 206R) and lever 299 (for rod 266L). The lever 208 is provided with a pivot 21b which is connected by an adjustablelength tie-rod 211 to a pivot 212 on the downwardly extending end 213 of the lever 209. The rod 211 is threaded at the left end, as shown in FIGURE 6, so as to provide spaced nuts 214 and 21.5 and on this portion of the rod there is a small block 216 which slides freely on the rod. Between the block 216 and the nut 214 there is interposed a spring 217 and similarly between the block 216 and the nut 215 there is another spring 218. The net result of this is that when the lever 208 moves arcuately its motion is transferred to the lever 209, but there is enough springiness in the connection so as to per- Hill: at least some free motion of one lever relative to the other without binding.

The upper end of the lever 208 is provided with a pivot 226 which is connected to the clevised end 221 of the piston rod 222 which operates in the air cylinder 223. The air cylinder is provided with a collar at 224 upon which there are axially aligned stub shafts 225. The lever 209 is bifurcated and at its upper end has pivot apertures which receive the stub shafts 225. Accordingly when air is introduced into the cylinder 223, the cylinder and piston will be moved relative to each other thereby imposing on each of them a motion to move the levers 208 and 209 relative to each other at their upper ends to rotate shafts 206R, 2(l6L toward each other or away from one another, depending upon into which end of the piston air is supplied, cylinder 223 being a double action piston. When the air is introduced into the left end of the cylinder 223 as shown in FIG- URE 6 the levers 2% and 209 will be moved away from each other at their upper ends and consequently cause the bag holder jaws to be moved toward each other into a position to hold a bag on the spout 45.

Mounted on each of the shafts 206R, 206L are the bag holder jaws 226 and 227 respectively, said jaws extending in a downward direction from the levers :mounted on the shafts and then being curved inwardly toward the adjacent side of the spout 45. The end portions of the bag holder jaws adjacent the spout are shaped so as to conform with the curved outer surfaces of said spout as shown in dotted lines in FIGURE 5. The nd portion of the jaws which contact the spout are faced with rubber blocks as at 228 for jaw 226 and 229 for jaw 227. When air is thus introduced into the cylinder so that the jaws are moved to the position shown in FIGURE 6, the upper portion of the bag is held tightly against the lower end of the spout with a grip that is sufliciently tight so that the bag will be held to the spout even though the bag may receive a full load of product.

The carriage frame is moved toward the dumping station and thereby frees the bag clamps and associated elements permitting them to be moved in a downward direction, the bag holder jaws and levers in a clamped position extending around the bag clam-p mechanism when said bag clamp mechanism is in an elevated position.

On the bag holder jaw 226 there is an auxiliary safety device referred to as the no bag-no product switch V which provides a signal in the event that the jaw 226 moves against the spout 45 and no bag is in place. To mount the safety device that provides the aforementioned signal, an aperture 232 is formed through the lower end of the jaw 226 and through the rubber block 228. The

lower end of the jaw is provided with a pivot recess 234 and in this is placed the safety device V which includes a microswitch 235 provided with a probe 236 which extends outwardly to a position somewhat beyond the face of the rubber block 228. The spout 45 is provided with an aligned aperture 238 so that the probe 236 can protrude into the spout through the aperture 238 in the event a bag is not in place. The micro-switch 235 is connected through its cable 239 into the electric circuit of the machine.

The probe 236 will normally extend outwardly beyond the rubber 228 and if a bag is not in place and jaw 226 is moved into gripping position against the spout 45, the probe 236 will protrude into the aperture 238 of the spout thereby retaining the micro-switch 235 in a position such that in conjunction with other electric circuitry to be described, the scale will not discharge the product. If a bag is in place, the material of which the bag is composed has sufiicient strength so that the probe 236 is moved to the full line position in FIGURE 6A to set the microswitch for continued operation of the machine. A no bag-no product switch W similar to switch V is provided on the lower end of jaw 227, said switch W operating in a similar fashion as switch V. The control cables 23% on the micro-switches are connected to a conduit 24]. and thence through a suitable conduit 242 to the control panel CA of the machine (see FIGURE 7).

Machine Control Apparatus Referring to FIGURE 16, the machine is supplied by air under pressure via line 251 which is supplied with a filtration lubrication and air pressure control unit shown generally under the bracket 252. The air under pressure is then introduced to the manifold line 254- which has thereon the junctions 255, 256, and 257.

For the control of air under pressure there are provided a bank of solenoid operated valves 1, J, K, and L. The valves I and L are identical four-way valves, the air flow pattern of valve I when its solenoid is energized being shown in subsidary FIGURE 16 1B and in 16 IA (when the solenoid is de-energized). Similarly the valve L is solenoid operated, its two operating positions, as the solenoid energized position being shown in FIG- URE 16 LB, and the solenoid de-energized position being shown in FIGURE 16 LA.

The valves I and Kare likewise identical and have two operating positions. When the solenoid for valve J is energized the air flow is as shown in FIGURE 16 IA, and when said solenoid is de-energized the how is as shown in FIGURE 16 JB. Valve K likewise has two operating positions, the air flow pattern being shown in FIGURE 16 KA when the solenoid is energized and 16 KB when the solenoid is de-energized.

From junction 257 a line 264 extends to one of the ports of the valve L. From another port of the valve of the cylinder 223 a line 261 extends to the fourth port of the valve L.

V-alve I "likewise has four ports, one of these being connected via line 258 to the air pressure supply line at junction 255. From another of the ports of valve I the air line 259 extends to the exhaust. From still another port on the valve 1, the line 266 extends to the junction 268 and thence one branch extends to the lower end of each of the cylinders 198R and 198L. From the upper ends of the cylinders IESR and ESL lines extend to the junction 267 and thence via line 269 to the fourth port of the valve I.

From the junction 256 on the air supply line an air circuit extends via line 253 to junction 271 and thence via line 272 to the inlet port of the valve J. Similarly, a line 274 extends from junction 271 to the inlet port of the valve K. From the exhaust port of the valve I 12 line 275 extends to the exhaust line 259 and from the exhaust port of the valve K the line 276 likewise extends to the exhaust line.

From the service outlet port of the valve K, a line extends at 273 to the inlet of master valve 279, which, when air is supplied via line 278 will move the controlled port of that valve to the on position. Likewise when air is exhausted from line 278 the valve 279 will move to the closed position. Similarly from the service outlet port of the valve J a line extends at 281 to the inlet port of the master valve 282. When air is supplied via line 281 the master valve 282 will be moved to the on position, thereby opening the circuit through its controlled side. When air is exhausted from the line 281 the master valve 282 will move to the closed or off condition.

A motor driven exhaust pump 66, which has a motor 66a connected through coupling 61 to the pump portion (see FIGURES 2, 3, 7, and 11) serves to supply negative pressure to the line 264a which is connected via junction 285 to the line 286 that extends to the outlet side of the master valve 279 and via line 237 to the outlet side of the valve 232. From the inlet port of the valve 279 a line 2% extends through junction 288, line 295 and junction 296 to the suction devices 122A and 122B and to the suction device 121i on the bag pick-up mechanism. Similarly from the controlled port 298 of the valve 282 a line extends at 299 to the suction device 154 on the bag opening mechanism.

From junction 288 on the line 294, the line 289 extends to the service port of a vacuum operated diaphragm control 290 which has an operating stern 2S1. When a vacuum is applied to the line 289 the stem is retracted and the switch 292, operated thereby, is closed. When no vacuum is applied to the line 289 the operating stem 291 is extended and opens the switch 292.

When the solenoid of valve L is energized the circuit extends and permits air under pressure to flow via the how connections as shown in FIGURE 16 LB to line 261 and thence to one end of cylinder 223, the other end of cylinder 223 being then exhausted via line 269 to the exhaust manifold. When this occurs, the bag holder jaws 226 and 227 are brought into engagement against the lower end of the spout to hold the bag firmly in place 4 until valve L is de-energized, the bag having previously been slipped onto the spout by the bag lifting mechanism. Similarly when the valve L is de-energized air will be introduced into the opposite end of cylinder 223 via the circuit connections as shown in FIGURE 16 IA and the line 261 will be exhausted. Thereu-pon bag holder jaws 226, 227 will be moved to the open or disengaged condition.

When the solenoid valve I is energized, air will be introduced via the line 269 to the upper ends of the cylinders 198R and 198L thereby positively closing the bag clamps 1931, and 193R. When this occurs the bag is firmly gripped and is ready to be lifted and slipped onto the lower end of the spout 45. Similarly, when the solenoid valve I is de-energized, air is introduced from line 258 to line 266 and thence through junction 268 to the lower ends of the cylinders 198R and 198L thereby causing the bag clamps 193L and 193R to be moved to an open position.

When solenoid valve K is energized, air under pressure is introduced via line 278 to the pilot valve 279 and it will open, thereby connecting the vacuum devices 122A-l22B to be exhausted via line 295, junction 288, line 294, line 286, junction 2 85, and line 264a to the vacuum pump 66. When valve K is de-energized air is exhausted from line 278, thereby closing the pilot valve 279. This shuts off the vacuum supply from the vacuum heads l2ti-il22A-1ZZB and leakage into the heads due to the imperfect contact of a bag with the head will render such vacuum devices incapable of thereafter gripping the bag. 

